NOx abatement in lean exhaust gas conditions over metal substrated zeolite catalysts

✍ Scribed by R.L. Keiski; H. Räisänen; M. Härkönen; T. Maunula; P. Niemistö

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 467 KB
• Volume: 27
• Category: Article
• ISSN: 0920-5861
• DOI: 10.1016/0920-5861(95)00207-3

✦ Synopsis

Metal substrated ZSM-5 zeolites ion-exchanged with copper are effective catalysts in the elimination of nitrogen oxides from lean automotive exhaust gases when propene works as a reductant. Some co-cations improve the catalytic activity of Cu-ZSM-5. The critical temperature for the deactivation of Cu-ZSM-5 catalysts is around 700°C where the state of copper begins to change resulting in the decrease of the catalytic activity. The structure of the Cu-ZSM-5 zeolite collapses after thermal aging at temperatures above 800°C. However, the coexistence of chromium in the zeolite increases the thermal stability of Cu-ZSM-5 considerably.